Written with Washington, D.C., lawyer Bruce Fein, Lon Snowden's message to his son also compares Edward Snowden to "Thomas Paine, the voice of the American Revolution, [who] trumpeted that a patriot saves his country from his government."

Those opinions contrast sharply with those of U.S. intelligence officials, who say the secrets about National Security Agency surveillance programs that Snowden has spilled to several news outlets have harmed national security.

Snowden is into his ninth day in the transit zone of Moscow's Sheremetyevo Airport. His U.S. passport has been revoked and he's seeking asylum in another country. As we reported earlier, he's asked more than 20 countries for asylum. But so far, none has said yes — and a growing list has said no.